Hi, what is the preferred way to reposition a GtkDrawingArea inside a GtkScrollbar just after the GtkDrawingArea has been enlarged? In detail: I have a DrawingArea (in Gtk 2.20 in Debian squeeze) that gets now and then enlarged when new elements are drawn on it. For enlarging it I use gtk_widget_set_size_request. The DrawingArea sits inside a Scrollbar. After enlarging the DrawingArea I want to make sure that the new element, which I've just drawn in the new region, is visible. I therefore call gtk_adjustment_clamp_page on both scroll bars with appropriate lower and upper values. I then call gtk_widget_queue_clear on the DrawingArea and let it redraw when the exposure event arrives. The trouble is that the new element is often outside the visible portion of the DrawingArea. So gtk_adjustment_clamp_page does not work in this case. AFAICS the problem is that the size does not change immediately when I call gtk_widget_set_size_request and therefore the call of gtk_adjustment_clamp_page works with the old size. When the adjustments finally get the new size they forgot about my clamp_page request and the new region with the new element in it remains invisible. When and how should I change the adjustments so that the new region in the DrawingArea becomes visible? Using the size-allocate signal does not work, because apparently it is only emitted if my size request is larger then the current size. (Sometimes I also delete elements and shrink the DrawingArea. But also in these cases I want to ensure that a certain current element is visible). Changing the adjustment in the handler of the exposure event does also not work reliably. Sometimes the DrawingArea receives exposure events before the size has changed. Therefore I would have to set the adjustment on every exposure event, which would break the function of the scroll bars. For screen shots of my application visit http://askra.de/software/prooftree/ . I posted this already on gtk-app-devel, but got no replies there. Bye, Hendrik Tews _______________________________________________ gtk-list mailing list gtk-list@xxxxxxxxx http://mail.gnome.org/mailman/listinfo/gtk-list
